* {
    box-sizing: border-box;
}
html {
    font-family: $font-family;
}
body {
    margin: 0;
    color: #333;
}
a {
    text-decoration: none;
    color: $gray-dark;
    cursor: pointer;
    -webkit-tap-highlight-color: rgba(255, 255, 255, 0);
    -webkit-user-select: none;
    -moz-user-focus: none;
    -moz-user-select: none;
}
ul {
    margin: 0;
    padding: 0;
    list-style: none;
}
h1,
h2,
h3 {
    margin: 0;
    padding: 0;
}
em {
    font-style: normal;
}
.icon {
    width: 1em;
    height: 1em;
    vertical-align: -0.15em;
    fill: currentColor;
    overflow: hidden;
}
//清除表单元素outline
input:focus,button:focus, textarea:focus {
    outline: none;
}
input,button,textarea {
    outline: none;
}
